X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=guestfish-actions.pod;h=7b5a4bed6d959d2aef75baad36e52dfd46ab5fdc;hp=c31905a98110a8a6b89ebd24e067883e9f7e136e;hb=d901cc916102f1aaccfb73396b48aa303e5b8cd7;hpb=9222136ac9b2e404dba128b1ac74dacaa8bf1038

diff --git a/guestfish-actions.pod b/guestfish-actions.pod
index c31905a..7b5a4be 100644
--- a/guestfish-actions.pod
+++ b/guestfish-actions.pod
@@ -372,6 +372,13 @@ The first element is the name of the program to run.
 Subsequent elements are parameters.  The list must be
 non-empty (ie. must contain a program name).
 
+The return value is anything printed to I<stdout> by
+the command.
+
+If the command returns a non-zero exit status, then
+this function returns an error message.  The error message
+string is the content of I<stderr> from the command.
+
 The C<$PATH> environment variable will contain at least
 C</usr/bin> and C</bin>.  If you require a program from
 another location, you should provide the full path in the
@@ -383,6 +390,10 @@ correct places.  It is the caller's responsibility to ensure
 all filesystems that are needed are mounted at the right
 locations.
 
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =head2 command-lines
 
  command-lines 'arguments ...'
@@ -390,6 +401,10 @@ locations.
 This is the same as C<command>, but splits the
 result into a list of lines.
 
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =head2 config
 
  config qemuparam qemuvalue
@@ -429,6 +444,19 @@ There is no comprehensive help for this command.  You have
 to look at the file C<daemon/debug.c> in the libguestfs source
 to find out what you can do.
 
+=head2 dmesg
+
+ dmesg
+
+This returns the kernel messages (C<dmesg> output) from
+the guest kernel.  This is sometimes useful for extended
+debugging of problems.
+
+Another way to get the same information is to enable
+verbose messages with C<set-verbose> or by setting
+the environment variable C<LIBGUESTFS_DEBUG=1> before
+running the program.
+
 =head2 download
 
  download remotefilename (filename|-)
@@ -456,6 +484,15 @@ Setting C<whattodrop> to 3 should drop everything.
 This automatically calls L<sync(2)> before the operation,
 so that the maximum guest memory is freed.
 
+=head2 equal
+
+ equal file1 file2
+
+This compares the two files C<file1> and C<file2> and returns
+true if their content is exactly equal, or false otherwise.
+
+The external L<cmp(1)> program is used for the comparison.
+
 =head2 exists
 
  exists path
@@ -509,6 +546,15 @@ Checking or repairing NTFS volumes is not supported
 
 This command is entirely equivalent to running C<fsck -a -t fstype device>.
 
+=head2 get-append
+
+ get-append
+
+Return the additional kernel options which are added to the
+guest kernel command line.
+
+If C<NULL> then no options are added.
+
 =head2 get-autosync
 
  get-autosync
@@ -569,6 +615,17 @@ This returns the verbose messages flag.
 This command installs GRUB (the Grand Unified Bootloader) on
 C<device>, with the root directory being C<root>.
 
+=head2 hexdump
+
+ hexdump path
+
+This runs C<hexdump -C> on the given C<path>.  The result is
+the human-readable, canonical hex dump of the file.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =head2 is-busy
 
  is-busy
@@ -757,7 +814,7 @@ as necessary.  This is like the C<mkdir -p> shell command.
  mkfs fstype device
 
 This creates a filesystem on C<device> (usually a partition
-of LVM logical volume).  The filesystem type is C<fstype>, for
+or LVM logical volume).  The filesystem type is C<fstype>, for
 example C<ext3>.
 
 =head2 mount
@@ -820,6 +877,15 @@ Some internal mounts are not shown.
 This moves a file from C<src> to C<dest> where C<dest> is
 either a destination filename or destination directory.
 
+=head2 ping-daemon
+
+ ping-daemon
+
+This is a test probe into the guestfs daemon running inside
+the qemu subprocess.  Calling this function checks that the
+daemon responds to the ping message, without affecting the daemon
+or attached block device(s) in any other way.
+
 =head2 pvcreate
 
  pvcreate device
@@ -892,6 +958,19 @@ command.
 
 Remove the single directory C<path>.
 
+=head2 set-append | append
+
+ set-append append
+
+This function is used to add additional options to the
+guest kernel command line.
+
+The default is C<NULL> unless overridden by setting
+C<LIBGUESTFS_APPEND> environment variable.
+
+Setting C<append> to C<NULL> means I<no> additional options
+are passed (libguestfs always adds a few of its own).
+
 =head2 set-autosync | autosync
 
  set-autosync true|false
@@ -936,9 +1015,6 @@ Set the path that libguestfs searches for kernel and initrd.img.
 The default is C<$libdir/guestfs> unless overridden by setting
 C<LIBGUESTFS_PATH> environment variable.
 
-The string C<path> is stashed in the libguestfs handle, so the caller
-must make sure it remains valid for the lifetime of the handle.
-
 Setting C<path> to C<NULL> restores the default path.
 
 =head2 set-qemu | qemu
@@ -953,9 +1029,6 @@ configure script.
 You can also override this by setting the C<LIBGUESTFS_QEMU>
 environment variable.
 
-The string C<qemu> is stashed in the libguestfs handle, so the caller
-must make sure it remains valid for the lifetime of the handle.
-
 Setting C<qemu> to C<NULL> restores the default qemu binary.
 
 =head2 set-verbose | verbose
@@ -1012,6 +1085,35 @@ C<path> should be a file or directory in the mounted file system
 
 This is the same as the C<statvfs(2)> system call.
 
+=head2 strings
+
+ strings path
+
+This runs the L<strings(1)> command on a file and returns
+the list of printable strings found.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
+=head2 strings-e
+
+ strings-e encoding path
+
+This is like the C<strings> command, but allows you to
+specify the encoding.
+
+See the L<strings(1)> manpage for the full list of encodings.
+
+Commonly useful encodings are C<l> (lower case L) which will
+show strings inside Windows/x86 files.
+
+The returned strings are transcoded to UTF-8.
+
+Because of the message protocol, there is a transfer limit 
+of somewhere between 2MB and 4MB.  To transfer large files you should use
+FTP.
+
 =head2 sync
 
  sync
@@ -1162,6 +1264,11 @@ As a special case, if C<size> is C<0>
 then the length is calculated using C<strlen> (so in this case
 the content cannot contain embedded ASCII NULs).
 
+I<NB.> Owing to a bug, writing content containing ASCII NUL
+characters does I<not> work, even if the length is specified.
+We hope to resolve this bug in a future version.  In the meantime
+use C<upload>.
+
 Because of the message protocol, there is a transfer limit 
 of somewhere between 2MB and 4MB.  To transfer large files you should use
 FTP.
@@ -1176,3 +1283,18 @@ How many blocks are zeroed isn't specified (but it's I<not> enough
 to securely wipe the device).  It should be sufficient to remove
 any partition tables, filesystem superblocks and so on.
 
+=head2 zerofree
+
+ zerofree device
+
+This runs the I<zerofree> program on C<device>.  This program
+claims to zero unused inodes and disk blocks on an ext2/3
+filesystem, thus making it possible to compress the filesystem
+more effectively.
+
+You should B<not> run this program if the filesystem is
+mounted.
+
+It is possible that using this program can damage the filesystem
+or data on the filesystem.
+